Since the emergence of zero waste concept, efficient waste recycling system and recovery of energy from the waste materials become challenging tasks globally. Municipal solid waste (MSW) is considered as one of a potential sources of energy. In the present study, bio-compactable iron oxide (Fe₃O₄) nanoparticles (NPs) were synthesized by hydrothermal method. These NPs were characterized by using atomic force microscopy (AFM), energy dispersive x-ray (EDX), and scanning electron microscopy (SEM) for size determination and surface morphology. The organic fraction of MSW (OFMSW) such as food waste (FW) was utilized as a substrate in this study. The anaerobic digestion of OFMSW in batch test was carried out under mesophilic temperature (37 ± 0.5°C). Four different concentrations of Fe₃O₄ NPs i.e 50mg/L, 75mg/L, 100mg/L, and 125mg/L were added in each batch test. It was observered that 75mg/L yielded maximum CH₄ and followed by 50mg/L.

The exploitation and harnessing of renewable energies are becoming increasingly important throughout the world. This study presents a method of methane (CH₄) generation using biological disintegration of food waste (FW) by anaerobic digestion (AD). The CH₄ production was enhanced by the addition of three different types of iron oxide (Fe₃O₄) nanoparticles (NPs) (Cetyletrimethlebromide (CTAB), urea-capped Fe₃O₄ NPs and Fe₃O₄ NPs without capping). The bio generation of CH₄ and biodegradation of volatile solids (VS) were carried out in an AD treatment at mesophilic conditions (35–37 °C) for more than 50 days in batch mode. The concentration of all three types of NPs was kept constant at 75 mg/L. It was noticed that urea-capped NPs produced the maximum CH₄ (5.386 L), followed by Fe₃O₄ NPs (5.212 L). Methane production in the control bioreactor was 2.143 L. The experimental results of CH₄ generation (a dependent variable) were analyzed against the concentrations of NPs used (as independent variables) in multiple regression analysis (MRA). The overall model for the experiments resulted in R² and R-adjusted values of 0.995 and 0.993, respectively.